Selective dual aileron control for aircraft



Jan- 5, 1954 F. F. cRocoMBE ET AL 2,665,085

SELECTIVE DUAL AILERON CONTROL FOR AIRCRAFT 4 Sheets-Sheet l OriginalFiled June 13 1950 Jan- 5, 1954 F. F. cRocoMBE ET AL 2,665,085

SELECTIVE DUAL. AIiLERON CONTROL FOR AIRCRAFT Original Filed Ju`ne 13,1950 4 Sheets-Sheet 2 Hffar-r) ey Jam 5 1954 F. F. cROcoMBE ET AL2,665,085

SELECTIVE DUAL AILERON CONTROL FOR AIRCRAFT original Filed June 15, 195o4 sheets-sheet s Jan- 5, 1954 F. F. cRocoMBE ETAL 2,665,085

SELECTIVE DUAL AILERON CONTROL FOR AIRCRAFT Original Filed June 15, 19504 Sheets-Sheet 4 Patented Jan. 5, 1.954

sELEoTrvE-DAL AILERON ooN'rRoL `I-Amormrr Y f FOR Y Frederick F.Crocombe, Gerrards Cross, England, and Geoffrey T. Hill, Londonderry,Northern Ireland,`assignors to Blackburn and General Aircraft Limited,Brough,-1England, a British company Original applicataionA .lu-ne` 13,l1950, Serial No. f 167,71'8.' Divided and this application November 27,1951, Serial No. 258,1?12

This application is a division of our abandoned :application Serial No.y167,718, led `June-V13, 1950.

the wings may be swung back `from a lowfspeed flight condition in whichthey are spread substantially normal to the aircraft centre line to ahigh speed flight condition'in which they are swept back at an acuteangle to give a delta shape wing plan form.

In the low speed range withthe wings spread appreciable movementsarerequired of control surfaces governing the lateral trim of theaircraft but in the high speed 'range much' smaller movements aresufficient and therefore the pilot might excessively move the'control'surfaces unless means are vprovided for limiting his movement on theactuating control.

Now one object of the present invention isto provide an aircraft havinghinged Wings in which f each wing is provided with two lateral controlsurfaces one for use in the low speed range and the other for use in thehigh speed range and the appropriate control Ysurface is automaticallybrought into controllable'` operation` by the movement of the wingsfrom. oneflightv conditionto theother. f

A further object of the invention is toiprovide such an aircraft inwhich the operating mechas, claims; (c1. 244-49) i nism controllingtherespective lateral control surfaces is such that equal vmovement of.the

pilots actuating control effects proportional movements of the controlsurfaces, i.,e.A a move.- ment which will give a large movement to thecontrol surface for` low speed flight will give a proportionately smallmovement to the control surface for high speed ight according to whichcontrol surface is at that vtime effective without requiring anyadjustment by the pilot.

To these ends according to the presentvinvention, the aircraft hashinged wings of the nature set forth and each wing has a pivotallymounted tip operable for lateral control at high speed only when thewings are swept back and a trailing edge aileron operable for lateralcontrol at low speed only when the wings are spread.

Further according to the present invention, the wing tip and thetrailing edge aileron-.are operated through a mechanism connected to afixed point eccentric -to Ythe hinge axis ofthe wing such that-themechanism is conditioned to actuate the appropriate control surfaceautomatically' on movementrof the wing fromspread to sweptback positionandvice versa. Y v

- Still vfurther-according to the present inven- Y 2 tion, the mechanismcontrolling the pivotal 'movements'ofthe wing tip and trailing edgeaileron incorporates levers such that equal movements of an actuatingmember gives proportional ymovements of the. operable control surface,i. e. large angular movements to the aileron or small rotationalmovements to the wing tip.

According tov yet another feature of the invention the movements of anactuating member are taken to a rockable elongated slotted memberandlevers operatively connected to the wing tip and aileron respectivelyengage in the slot of such member which isk itself connected for bodilymovement to a fixed point eccentric to the hinge axis of the wing suchthat rocking of the slotted member moves the lever operating the onecontrol surface when its fulcrum is concentric with 'the point ofengagement of the lever of the other control surface and the slottedmember is moved lbodily as the wing is moved from its one position ,tothe other to change the operation from the one such lever to the other.

Throughout this specioation high speed and low speed are relative termsand the latter means the speed of flight at take off up to cruisingspeed whilst the former means higher speeds into the sonic region.

'4 Now in orderv that the invention may be clearly understood andreadily carried into effect, an embodiment thereof is, by Way ofexample, hereinaftervmore fully described with reference to theaccompanying drawings which are given for purposes of illustration onlyand not of limitation.

In-thesedrawings:

Figure 1 is a fragmentary sectional plan view showing the aircraft Withits wings spread and illustrates the operating gear controlling themovable wing tip and trailing edge aileron,

Figure 2 is a View similar to Figure l with the Wings swung back totheir swept-back position,

Figure 3 is a detail view on a larger scale showing the mechanism foralternatively operating the movable wing tip and the trailing edgeaileron with the mechanism in the position to lock the Wing tip andallow movement of the aileron as when the wing is spread,

Figure 4 is a View on the line IV-IV of Figure 3, and l* Figure 5 is aview similar to Figure El with the mechanism in alternative position tolock the aileron and allow movement of the movable wing tip as when thewing is swept back. Referring now v'to the said drawings, and inparticular to Figures 1 "andZ thereof, the invention is illustrated asapplied to an aircraft of the 3 nature of that described in UnitedStates patent application Serial No. 167,718, and now abandoned, andliaving-'gainf-elongated; fuselagey I ..vvith a lateralzextensin' Qneachgsid within/Which is pivoted at l a wing 5 which is mounted to becapable of swinging movement about the hinge l from a spread positionsubstantially normal to the longitudinal axis of theaircraft"als-illustrated 4 trailing edge aileron I9 is displaced for thepurpose of lateral control of the aircraft, that displacement,is-pptogressivelyproportionally transifierr-editoatheiotliercontrol.surfaeeiautomatieally 5 with the movement of the wing and theformer in Figure l, to a swept-back position inwhichrofscri-bedgaregin-texmsgof the two control surfaces the Wings 5are sharply svvept-lgackatlafnacute angle and with theextensioiisgiimakegupa ng plan of substantiallycleltaifornnlasillustrateddn Figure 2. The rear endofl-t'lae'lfuselage-rIacarries an all-moving surface empennage 6comprising a short iin supporting pyotallyhnlo Ipldsigailgh.

planes at a dihedral angle. Armi-bol- .eM L. 1s provided within thefuselage in the region oftlle centre of gravity and the efllux pipe fromsuch engine extends out through the rear extremity'of the fuselage,whilst combustion air is taken in at y.intakes at'rthelfront tot. thefuselage.

:Eachl Wing 1 terminates inra ',pivotallydmounted Wing -tipuaileron E13.i and Lis.: ialso l .provided .with ca hinged.rtrailingsedgeaaileron4.9. The lshafts-4,20 4(:see also. liigureslnand 5 i1ofl thelwingtipfflmas appropriately restored to its Zero position in which it isnally held during continued effective operation-oftlie-other controlsurface.

LJIhe movements of the parts as already deijrbeing li,.'a,t,lieirzeroyposition. In this position one ,clcontrolasurfaceiisifreeto move whilst the other `:thas:itsfoperatin-g-parts at the dead centreposition so thatino-movement occurs and it is virtu- 1f changeover ofthe Wing position and .ihenceoiathe control surface occurs while theoperablepoptrol surface is displaced there is a displacement of slottedmember 2l which is maintained during the change and there is hence aproportional displacement of the Ainevv-ly,effe ctveVcontrol-surfacewhilst the operatingY parts of xrthe `other-reaolivzerolocked position.

-Thewing position maythusfbe changed with- 25 `out havingfirst to=Zeroise the'lateralcontrol sur- :a lever l 2 I fast. thereon4`vlliichi. is .l connectedsbyb-.a

link 22 to.a bellfcrankrleverZS. Similarlyfthe operatingmemberemaof-rthe saileron`I9,-is conlnectedas-:through-.adink 25 to.abellcrank lever 226. The free.limbofitheibellcrank leversr23, ;26V'engage in -:the slot; 1of.i.an .elongated .2 member :2-'I :whichistaty .one .Y end. :2l :connected Lto. a.. parti 2 8 which isconnectedtc ai-leveri29 tolwhichwisf-also connected an operating irode30 movable Munder Athe-pilotis control. '-z-T'her elongatedA slottedmember` 2 l ,(seeFig.: 4) .isalso.v `connected inl. anyfsuitablemar-mencion example, hy .usual pivotal; connections, .to ione-end ofapart I3| :theP other end `of which .convenientlyi pivots .on`theiaxiscf .the Alever i 2.9 l and this .ipart a3 I .iis intermediateits Jength; connectedebyla vlinkiill-iov onetlimb :13 I 1 llof a bellcrank lever 33, the other limb 3.32. of which is connected; by arodiilli toga fixed part: 3.51y of the `aircraft.fuselage;feccentrilz;tosthe vhinge/:lll of the Wingi.

-vl-.Thus `.Whenllthe Wingsiarespread; thel mechanism is in the positionillustrated'tiniligures .i1 and -andetheifulcrum cpoint.of: theelongated slotted member i2 1 is positioned over the. =end-.of

the: free limbt23 ofztheibell cranklever 23.so:that

:axialvmovement of ithecontrolrodf oinfrocking the elongatedlslotted-fmembero-Z'I rocks Y.the wbell crank leverl-.Zwtofeiectangular:displacementtof the trailing edge aileron I9 f-to..govern:lateral movementsof .-the aircraft.

"faces and the pilot does ynot-needto'make'any adjustment of v'hiscontrolv or alter the extent lfof operation lthereof during `"high vandvlow speed flight and changing from one to` the other.

The lengths of the controllsurfaces:operating 'membersnarnely'the lever2l and link, 22'effective on :the Wing tip I8 andoperatinglmemberd andlinkg25 effective on' theftrailing edge aileron I9 `are sodimensioned.thatv similar extents of movementof the yactuating controlrod fand hence of ,thepilotfs controlthrough therespective bellcrank'leversgZyjZ impart proportional and. different, moveinentsinthesame sense' to the ,controlsurfaces',` i., e. large angularlmoverrients it ,the trailing ledseeileron I9 and- Small rotational-mov'errients'` to the Wing tip`` I8.

llt iste bet-.understood,theinvention iS,11oi-,1i.m ited tn ,izhei.designzof aircraftlshown. the, .drawing as it; may beiappliedto .fariyfaireraft-havizig Mmes, Milioni-n1 'y Swing between Af-,Srireari andswept-back positions.

,-.We-claim: ...1.. An @aircraft hai/iris.any aileron .-.controlsystem'saidiaircrafthavingpiVOtaIly mounted Wings displaceable between,-a:. slow speed position ,vextending substantially normal to .the,center .f line ofathe airoraftand af. highispeed .swept back positiony.at -.an,:.acute..angle l. with 7respect toy said; cenlter line,.-.said -.aircraft.ha-ving pivotallyv ,mounted Asi the winga lmoves-.loackiintoi its; swept-back positionpthereccentric positioning.of .the.point135 of connection kof the1od.-34f.toitheffuselage Iwithrespectfto the hinge -aXis 2.4.ofathe wing 5 issuch thatthereis;a-.virtual movement., of :the rod,3bl,with,1'espectlto the Wing whichprogressively. `rocks-the `.bell ycrank lever 33 to move the part ".3 Iandihence, theelongated member;` 21,.funtil, the swept-.back positioniasiniFieureS and 5) :the ffulcrlumA of i the elongated slotted member21 coincides with the endrofathe ifree .limb..2 6 of the bell:crankgleverr- LZB when the movement of the control rod 30 through tothe elongated slotted-.-memherY-:N @causes @hat iiierribei .to-.rook thebellA crank ,le.ver 23 .gandfhence the lever 2 I torotatetheimovableirzine-iup l-felooutfthefaxis of its shaft 20.

fvrat thetimeewhen the Wiiisvfis movedifiiom `spreadtolswept-baoklpositienionviee versa, he operable control .lsu-riesca.eaWiris-.ti-p: t8 er the .-Wing tiptailercnsffor-.fuse .With.A said.Wings .in said .highspeed-- position andtrailing edge :ailerons in saidWings ;for usen/ith lsaid wings .in said v,loyv speed position, said@control .system comprising:

.60 aileron lcontrol means .gperablefby,aipilotsoilsaid aircraft;'Mi-ngf-,ti-p aileron vcontrol means connectedto varythe positionaofsaid Wing tiplailerons; trailing edge aileroncontrol ymeansconnectechtel vary; tha-position KVofsaid.trailing edge-ailer- @5 ons;linkage @means interconnecting :isaid .pilot operable ,aileron control.means, said '.vving tip aileronoontroLmea-ns and saidtrailinaedgeaileronfcontrolfmearis andadisposed selectivelyeto Qonileetfe112,heresaidswingitin aileron -..eo.ntr,o1.f, means 7,0 erisaidtrailing esige.L aileron eontroLmeans-lfer control said :pilot operablepaileron control means and means I responsive-. to ,the position ,ofSalm-wings and l connected l to said: linkage mea-ns for rendering saidselectivefconnectioneective 7,5 withrrespeetftosaid'wingatip,faileronswithflsaid wings in said high speed position andeffective with respect to said trailing edge ailerons with said Wings insaid low speed position.

2. A control system according to claim 1, further comprising: meansincluding said linkage means for selectively locking either said wingtip aileron control means or said trailing edge aileron control means ina predetermined xed position, either of said aileron control means whichis connected through said linkage means to said pilot operable controlmeans being unaffected by said locking means.

3. A control system according to claim 1, wherein said linkage meanscomprises a rst bell crank lever connected to said Wing tip aileroncontrol means; a second bell crank lever connected to said trailing edgeaileron control means, said bell crank levers each having a limb with afree end, said free ends being spaced apart; a

slotted link member; a movable fulcrum member f connected to said wingtip position responsive means and also connected to said slotted linkmember, and further connected to said pilot operable aileron controlmeans, said free ends of each of said bell crank levers comprising aportion slidably engaging said slot, said slotted link member beingmovable in response to said Wing tip position responsive means toposition said pivotal connection of said movable fulcrum membercentrally with respect to either of said free bell crank lever ends, theother of said free ends being disposed in one end of said slot forresponse to rotation of said slotted link member about said fulcrum.

FREDERICK F. CROCOMBE.

GEOFFREY T. HILL.

References Cited in the le of this patent UNITED STATES PATENTS NumberName Date 2,191,842 Back Feb. 27, 1940 2,209,863 Tupta July 30, 19402,316,885 Ortega Apr. 20, 1943 2,428,934 Grille et al Oct. 14, 19472,509,272 Karnuth et al May 30, 1950 2,534,764 Focht Dec, 19, 19502,538,602 Taylor et al Jan. 16, 1951 FOREIGN PATENTS Number Country Date691,665 Germany June 3, 1940 917,753 France Jan. 21, 1947

